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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
351

Messagingová infrastruktura a produktová analýza trhu / Message infrastructure and market analysis

Klimeš, Ivo January 2008 (has links)
There are considered modern messaging architectonical concepts SOA and EDA in this diploma thesis. There are presented the elementary principals of functioning of these paradigms and principals are given into the wider context with the business processes and IT Governance. The aim of this thesis is to compare two preselected software solutions of the operational monitoring. There is always one solution per architectonical style and predefined comparative criteria. This thesis is divided into five consequential parts. The first part is focused on the putting the modern architectures into the historical context. The historical context is the way out for the modern architectonical styles. The part afterwards is closely focused on the concepts of SOA and EDA, and also on the comparison of the mentioned architectonical styles. There are put the concepts into the connection with business processes and maturity models In the next chapters. That all together has a influence on the successful implementation and governance. The chapters continuously flow into the last theoretical part of the thesis, IT Governance. There are described all the elements connected with the successful IT systems operating based on the paradigm SOA or EDA. The context in the practical part is link to the all these previous chapters. There are selected and described two software solutions in the practical part of this thesis. These solutions are then compared by the predefined criteria. The conclusion summarizes all the knowledge acquired during the paradigm comparison and there are also summarized knowledge acquired during the comparison of selected monitoring products.
352

Analýza souvislostí mezi self-efficacy, kapitálem, plánováním a ambicemi začínajících podnikatelů v České republice / Analysis of the link between self-efficacy, capital, planning and ambition of nascent entrepreneurs in the Czech Republic

Mareš, Jan January 2011 (has links)
The thesis is based on data from the Global Entrepreneurship Monitor project and analyzes the link between self-efficacy of Czech nascent entrepreneurs and the disposable amount of human, social and financial capital. It also examines the link between self-efficacy and planning activities of nascent entrepreneurs. The second part of the paper analyzes the relationship between growth ambitions of nascent entrepreneurs and disposable human, social, financial capital and business planning. It also shows the relationship between entrepreneurial self-efficacy and growth aspirations of Czech nascent entrepreneurs.
353

Uso do espalhamento de luz para o estudo do efeito de uréia sobre agregados supramoleculares e monitoramento do peso molecular em reações de polimerização / Use of light scattering to study the effect of urea about supramolecular aggregates and monitoring of the molecular weight in polymerization reactions

Fábio Herbst Florenzano 18 June 1999 (has links)
Nesta tese, dois projetos distintos que usaram a técnica do Espalhamento de Luz foram desenvolvidos. Estudou-se a influência de soluções concentradas de uréia sobre agregados supramoleculares de anfifilicos (ASA\'s), através de condutimetria, supressão de fluorescência e espalhamento de luz. A uréia causou aumento da concentração micelar crítica (CMC) em todos os sistemas micelares estudados. A uréia diminuiu a seletividade da ligação iônica entre cloreto e brometo em micelas de haleto de cetil-trimetil-amônio, estudada através de supressão de fluorescência. Este aditivo causou também aumento na segunda CMC de brometo de tetradeciltrimetil- amônio (TTAB) e diminuição do peso molecular das micelas em bastão formadas. Concluiu-se, desta primeira parte, que a uréia tende a interferir nas transições de fase apresentadas em sistemas micelares, provavelmente através da combinação dos mecanismos direto e indireto. A uréia apresenta potencial para uso como aditivo para modulação das propriedades estruturais de sistemas micelares. Na segunda parte da tese desenvolveu-se um sistema, baseado em espalhamento de luz, capaz de monitorar o peso molecular de polímeros durante a polimerização. O sistema foi eficiente no monitoramento da polimerização da N-vinil-pirrolidinona, mostrando que o peso molecular do polímero formado é constante durante a maior parte da reação. As teorias atuais de cinética de polimerização não foram capazes de explicar esse comportamento. / Light scattering techniques (static and dynamic) were used to detenninate the effect of urea on supramolecular aggregates and to monitor on-line molar mass ofpolymerization reactions. For the first set of investigation it was already established that urea increases the CMC and the dissociation degree (α) of ionic micelles (CTABr, TTABr, and SDS). From fluorescence suppression studies it was found that urea diminishes the ionic binding in zwitterionic and cationic micelles as well as in cationic vesicles. Bromide and chloride ionic selectivity in cationic micelles was found to nearly disappear in the presence of urea. Light scattering (static) detenninations showed that the weight averaged molecular weight (Mw) ofboth SDS and CTABr are invariant by the presence of the denaturant. A slight increase in the excluded volume tenn (A2) was detected for CTABr in the presence of 3M urea. In parallel both A2 and the radius of gyration (γ) of two polyelectrolytes (PAA and Hyaluronic acid) were not affected by the presence of urea. Sphere-to-rod concentration transitions (2nd CMC) of TIABr micelles increased in the presence of urea and the MW of rod particles were observed to decrease. For the insoluble mixture of CTABr/Polystyrenesulfonate solubilization was achieved in the presence of 3M urea. These set of results were explained as a result of the dual effect of urea, that is, the indirect effect by changing the properties of the solvent and the direct effect by solvating the hydrophilic domain of the aggregates and contributing with a stronger dipole moment. The second set of experiments was directed towards the real-time, on-line monitoring of Mw of polymerization reactions. This new approach could be succeeded by the coupling a light scattering detector, an UV photometer and a differential refractometer on line with a HPLC system. Mw growth formed in the polymerization of N-vynil-pirrolidone was accomplished with a small inherent error. Within the studied conditions Mw reached a plateau at early polymerization stages, after that only an increase in the number of polymer kinetic chains was observed. Current kinetic models were unable to predict the observed Mw growth pattern. This system is of great importance in basic and technological applications by virtue of its on-line capability.
354

Etude de faisabilité d'un détecteur dédié à la discrimination bêta/gamma / Study of the feasibility of a detector dedicated to the beta/gamma discrimination

Luo, Yiyan 04 December 2018 (has links)
A des fins de propreté radiologique, les exploitants nucléaires doivent évaluer l'activité surfacique résiduelle, telle que la contamination bêta. Pour cela, les contaminamètres sont essentiels. Dans ce cadre, EDF R&D a proposé un projet de recherche visant à étudier la faisabilité d’un contaminamètre innovant permettant de détecter l’activité surfacique bêta in situ, alors qu’elle est actuellement mesurée ex-situ.L'objectif principal de ce travail est de détecter une contamination bêta surfacique de 0,4 Bq/cm^2 dans un environnement gamma élevé, jusqu'à 100 µSv/h. Cela exige un détecteur ayant une performance de discrimination bêta/gamma élevée. Plusieurs technologies basées sur un scintillateur et/ou un détecteur à gaz ont été étudiées. Des simulations Geant4 ont été effectuées pour optimiser la configuration des technologies retenues (géométrie, matériaux, etc.). Suite à ces simulations, deux prototypes, de type Phoswich, optimisés ont été fabriqués et testés à l’aide de sources bêta et gamma au laboratoire ( LPC Caen). En outre, deux campagnes d’essai ont été menées dans une centrale nucléaire (CNPE de Chinon) afin d'évaluer les performances des prototypes développés dans un bruit de fond gamma réaliste. Les simulations Geant4 et les tests sont discutés dans cette thèse. / For radiological cleanliness purpose, nuclear operators have to assess surface residual activity such as beta contamination. To this aim, contamination monitors are essential. In this context, EDF R&D proposed a research project in order to study the feasibility of an innovative contamination monitor to detect beta surface activity in situ which is until now performed ex situ. The main objective is to detect a 0.4 Bq/cm^2 beta surface contamination in a high gamma background up to 100 μSv/h. This demands the detector to have a high beta/gamma discrimination performance. Several technologies based on scintillator and/or gas filled detector have been investigated. Geant4 simulations have been carried out to optimise the configuration of the chosen detector such as geometry, materials, etc. Two simulation-optimised prototypes based on Phoswich detectors have been developed and tested with beta and gamma sources in a laboratory framework (LPC Caen). Furthermore, two experimental campaigns have been conducted in a nuclear power plant (NPP of Chinon) in order to evaluate the performance of the developed prototypes in a realistic gamma background environment. The Geant4 simulations and the experimental work are discussed in this thesis.
355

Vnímání textu z tištěné předlohy a obrazovky / Reader's perception of printed and displayed text

Piskáčková, Klára January 2016 (has links)
(in English): This thesis is conceived as a metareview of research on differences in perception, understanding and retention of text on various display media. It summarizes the results of the most interesting and most relevant research on this topic conducted since the 80s to the present. Even though it is difficult to summarize the results of individual studies, mainly because of differences in research methodology and differently chosen tested samples, we can say that the main finding of this metareview is that display technologies that are available these days have no negative effect on eye fatigue, reading speed, perception, understanding or retention of text. Theoretical part of this thesis is followed by practical part that consists of three short experiments performed on a small sample of participants. First of those experiments studies differences in reading comprehension and retention among high school students, second experiment focuses on differences in reading speed on different media and subjective evaluation of eye fatigue, and the third experiment is an online form about subjective preferences of study materials among learners.
356

Untersuchungen zur Einsatzmöglichkeit der Dreikantmuschel Dreissena polymorpha als biologischer Filter und Wasserhygienemonitor

Schröter-Bobsin, Ute 25 April 2005 (has links)
Dreikantmuscheln (Dreissena polymorpha) sind aufgrund ihrer speziellen Ernährungsweise in der Lage, erhebliche Wassermengen unterschiedlichster Qualität sehr effektiv zu filtrieren und dabei zu reinigen (Biofilter). Ziel der Arbeit waren Einschätzungen zum Leistungsumfang, der Nutzung und von Grenzen des Muschelfilters. Die Exposition der Muscheln erfolgte in der Elbe am Neustädter Hafen in Dresden (Oberflächengewässer), in dem ersten und zweiten Schönungsteich der Kläranlage Reichenau (Sachsen) und in einem Waldbad in Langebrück (Badegewässer). Eine wirksame Elutionsmethode war die Grundlage um Mikroorganismen (Bakterien, Viren und Parasiten) aus dem Muschelgewebe effizient nachweisen zu können. Die bakterielle Wiederfindungsrate von 86% und eine Wiederfindung von 97% für Bakteriophagen bestätigen die Elutionseffizienz des Verfahrens. Die Befähigung von Dreissena polymorpha zu einer saisonal beeinflussten Bioakkumulation gegenüber dem Umgebungswasser konnte durch ein Monitoring mit einem Anreicherungsfaktor für Bakterien von 87 (gemittelt) und für Bakteriophagen von 261 (gemittelt) eindrucksvoll bestätigt werden. Batchversuche im Labormaßstab bestätigten die im in situ - Monitoring ermittelte Bakterienakkumulation und demonstrieren darüber hinaus eine temperaturabhängige Inaktivierung (Elimination) der Bakterien (Intestinale Enterokokken) durch die Muscheln mit Reduktionsraten von -77% bei 20°C bzw. -61% bei 6°C. Nicht alle aufgenommenen Organismen werden durch die Muscheln inaktiviert. Das ergaben die in situ Sedimentuntersuchungen unter dem Muschelfilter. Die Verdopplung der Enterokokken sowie die erhöhten Werte der somatischen Coliphagen im Sediment unter Muschelbesatz charakterisieren dieses Kompartiment als Keimreservoir. Die bakterielle Besiedlung des Verdauungstraktes von Dreissena polymorpha wird stark durch die Bakterienzönose des umgebenden Wassers beeinflusst. Sowohl im Wasser als auch im Muschelgewebe dominierten fünf Bakterienstämme (Actinobacteria, Proteobacteria, Bacteroidetes, Firmicutes,"environmental group"). Eine auffallend hohe Dominanz zeigten die Mycoplasmen (Firmicutes), was auf eine mögliche ökologische Nische für Vertreter dieser Gattung in der Muschel hindeutet. In allen Muscheleluaten des Monitorings wurden Legionellen nachgewiesen. Die Muscheln des Teiches 2 der KA Reichenau zeigten mit 86% die höchste Kontamination aller Expositionsorte. Legionellenamplifikate im Muscheleluat 2 gingen kontinuierlich mit ebenfalls positiven Befunden im Wasser einher, so dass der Einsatz von Dreissena polymorpha auch im Biomonitoring von Legionellaceae möglich ist. Erstmalig wurden in der Elbe und im Abwasser der KA Reichenau E. coli O157:H7 infizierenden Phagen und deren Anteile nachgewiesen. Die Elbe lag mit einem E. coli O157:H7 infizierenden Phagenanteil von 7,5% deutlich über dem Rohabwasser (1,0%) und dem Zulauf zum ersten Schönungsteich der Kläranlage (0,5%). Der Stx Gennachweis im Muscheleluat war dagegen nur in einer von 24 Proben erfolgreich. Enterale Viren (AdV, EV) wurden in den Dreikantmuscheln und ihrem Umgebungswasser diskontinuierlich nachgewiesen. Enteroviren wurden im Wasser (57% gemittelt) häufiger als in der parallelen Muschelproben (10%) nachgewiesen. Parasiten (Giardia lamblia und Cryptosporidium parvum) werden durch die exponierten Muscheln aufgenommen, dies bestätigten die qualitativen Testergebnisse. In den Dreikantmuscheln wurde sowohl für G. lamblia (78%), als auch für Cryptosporidien (77%) eine durchschnittlich höhere Nachweisrate im Vergleich zu den korrespondierenden Wasserproben (42% und 36%) ermittelt. Die effiziente Akkumulation und die Umweltresistenz der Dreikantmuscheln sind hervorragende Eigenschaften, die sich zu einem zuverlässigen Biomonitor mit "Hygienegedächtnis" und hoher Sensibilität vereinen lassen.
357

Development and Integration of a Low-Cost Occupancy Monitoring System

Mahjoub, Youssif 12 1900 (has links)
The world is getting busier and more crowded each year. Due to this fact resources such as public transport, available energy, and usable space are becoming congested and require vast amounts of logistical support. As of February 2018, nearly 95% of Americans own a mobile cell phone according to the Pew Research Center. These devices are consistently broadcasting their presents to other devices. By leveraging this data to provide occupational awareness of high traffic areas such as public transit stops, buildings, etc logistic efforts can be streamline to best suit the dynamics of the population. With the rise of The Internet of Things, a scalable low-cost occupancy monitoring system can be deployed to collect this broadcasted data and present it to logistics in real time. Simple IoT devices such as the Raspberry Pi, wireless cards capable of passive monitoring, and the utilization of specialized software can provide this capability. Additionally, this combination of hardware and software can be integrated in a way to be as simple as a typical plug and play set up making system deployment quick and easy. This effort details the development and integration work done to deliver a working product acting as a foundation to build upon. Machine learning algorithms such as k-Nearest-Neighbors were also developed to estimate a mobile device's approximate location inside a building.
358

Sensorkaraktärisering kring delaminering

Paul, Sanjib January 2020 (has links)
Dagens industrier håller på att bli allt mer automatiserade, smartare och effektivare, i samband med detta ökas kraven att man tar fram noggrannare och pålitligare sensorsystem som är även kostnadseffektiva. Målet med denna undersökning har varit tillsammans med Iggesund Pappersbruk är att karakterisera noggrannheten för sensorn Ultrasonic Double sheet moniter (DSM) och även ta fram riktlinjer för en ingående inline mätande prototyp. Studien använder sig av väldigt enkla metoder för att karakterisera resolutionen och även undersöka det minimala avståndet för flera seriekopplade sensorer utan att de ingriper och stör varandras inläsningar. De programvaror som används under studien är PACTware och Matlab. Undersökningen visar resultat på en trovärdig noggrannhet utav sensorn och man har även kunnat karakteriserat detektions arean runt om receivern för den framtida prototypen. Avslutningsvis går studien igenom synpunkter på DSM sensorn och en diskussion om att karakterisa olika destruktiva ytor men även om vad som kan förbättras eller förbyggas. / Today's industries are becoming more automated, smarter and more efficient, and it requires high standards to develop more accurate and reliable sensor systems that are low-cost. The aim of this study was together with Iggesund Pappersbruk to characterize the accuracy of the Ultrasonic Double Sheet Monitor (DSM) sensor and to develop guidelines for an in-line measuring prototype. The study uses quite simple methods to characterize the resolution and investigate the minimum distance for several series-connected sensors without interfering with each other's readings. The software used during the study is PACTware and Matlab. The study shows results on a credible accuracy of the sensor and it has also been possible to characterize the detection area around the emitter for the future prototype. Finally, the study concludes with views on the DSM sensor and a discussion on how to characterize different destructive surfaces but also what can be improved or prevented.
359

Expressiveness and Decidability of Weighted Automata and Weighted Logics

Paul, Erik 19 October 2020 (has links)
Automata theory, one of the main branches of theoretical computer science, established its roots in the middle of the 20th century. One of its most fundamental concepts is that of a finite automaton, a basic yet powerful model of computation. In essence, finite automata provide a method to finitely represent possibly infinite sets of strings. Such a set of strings is also called a language, and the languages which can be described by finite automata are known as regular languages. Owing to their versatility, regular languages have received a great deal of attention over the years. Other formalisms were shown to be expressively equivalent to finite automata, most notably regular grammars, regular expressions, and monadic second order (MSO) logic. To increase expressiveness, the fundamental idea underlying finite automata and regular languages was also extended to describe not only languages of strings, or words, but also of infinite words by Büchi and Muller, finite trees by Doner and Thatcher and Wright, infinite trees by Rabin, nested words by Alur and Madhusudan, and pictures by Blum and Hewitt, just to name a few examples. In a parallel line of development, Schützenberger introduced weighted automata which allow the description of quantitative properties of regular languages. In subsequent works, many of these descriptive formalisms and extensions were combined and their relationships investigated. For example, weighted regular expressions and weighted logics have been developed as well as regular expressions for trees and pictures, regular grammars for trees, pictures, and nested words, and logical characterizations for regular languages of trees, pictures, and nested words. In this work, we focus on two of these extensions and their relationship, namely weighted automata and weighted logics. Just as the classical Büchi-Elgot-Trakhtenbrot Theorem established the coincidence of regular languages with languages definable in monadic second order logic, weighted automata have been shown to be expressively equivalent to a specific fragment of a weighted monadic second order logic by Droste and Gastin. We explore several aspects of weighted automata and of this weighted logic. More precisely, the thesis considers the following topics. In the first part, we extend the classical Feferman-Vaught Theorem to the weighted setting. The Feferman-Vaught Theorem is one of the fundamental theorems in model theory. The theorem describes how the computation of the truth value of a first order sentence in a generalized product of relational structures can be reduced to the computation of truth values of first order sentences in the contributing structures and the evaluation of an MSO sentence in the index structure. The theorem itself has a long-standing history. It builds upon work of Mostowski, and was shown in subsequent works to hold true for MSO logic. Here, we show that under appropriate assumptions, the Feferman-Vaught Theorem also holds true for a weighted MSO logic with arbitrary commutative semirings as weight structure. In the second part, we lift four decidability results from max-plus word automata to max-plus tree automata. Max-plus word and tree automata are weighted automata over the max-plus semiring and assign real numbers to words or trees, respectively. We show that, like for max-plus word automata, the equivalence, unambiguity, and sequentiality problems are decidable for finitely ambiguous max-plus tree automata, and that the finite sequentiality problem is decidable for unambiguous max-plus tree automata. In the last part, we develop a logic which is expressively equivalent to quantitative monitor automata. Introduced very recently by Chatterjee, Henzinger, and Otop, quantitative monitor automata are an automaton model operating on infinite words. Quantitative monitor automata possess several interesting features. They are expressively equivalent to a subclass of nested weighted automata, an automaton model which for many valuation functions has decidable emptiness and universality problems. Also, quantitative monitor automata are more expressive than weighted Büchi-automata and their extension with valuation functions. We introduce a new logic which we call monitor logic and show that it is expressively equivalent to quantitative monitor automata.
360

A Case Study on the Process of Passing a Radiography Registry Examination

Chamberlain, Encarnita Antonia 01 January 2015 (has links)
This project study addressed the problem of the low percentage of a Mid-Atlantic university's radiography graduates passing their credentialing registry examination. The cohort had a 2014 pass rate of 83% while the majority of surrounding schools had pass rates of 100%. In order to become registered radiographers, graduates must be able to take what they have learned in their educational program and directly apply it to their professional skill set. The conceptual framework for the study was social constructivism, adapting and transforming what was new information to previous experiences and group activities. A qualitative case study research design was chosen, and interviews were conducted with 9 graduates from the 2014 radiography cohort. The interviews were recorded, transcribed, manually coded, and analyzed for emerging themes. Key results indicated the graduates needed to self-monitor, self-motivate, and self-propel to successfully pass their credentialing exam. A 3-day professional development plan for graduates was created based on the findings from the study. Passing the credentialing exam affects social change in that knowledge and education produces positive outcomes, and for allied health professionals, it produces optimum patient care. Social change is possible through education, which will enhance an individual's self-efficacy, thereby enriching the society and culture to which they contribute. This knowledge will support the local problem in that optimum performance for radiography graduates will be monitored for standards of excellence.

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